<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    #text {
      color: rgb(0, 0, 0);
      font-size: 40px;
      font-weight: bolder;
    }

  </style>
</head>

<body>
  <div id="app">
    <p id="text">{{msg}}</p>
    <button @click="reverseMsg">逆转世界</button>
  </div>

  <script src="./vue.js"></script>
  <script>
    const app = new Vue({
      el: '#app',
      data: {
        msg: 'Hello,world'
      },
      methods: {
        reverseMsg() {
          this.msg = this.msg.split('').reverse().join('')
        }
      }
    })
  </script>

</body>

</html>